JPH073160A - Room-temperature-curing organopolysiloxane composition - Google Patents

Abstract

PURPOSE:To obtain the composition excellent in rapid curability and depth curability and also in workability. CONSTITUTION:The composition comprises an organopolysiloxane terminated with a hydrolyzable silyl group, a polymer of an ethylenically unsaturated monomer, a carbonylated organic compound, an organic compound having a primary amino group, and a curing catalyst for the above organopoly-siloxane.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is used as a sealing material for coating, a coating material, a sealing material for electric / electronic parts, a potting material, a fiber treating agent, an adhesive for automobiles, construction and electric / electronics. It relates to a useful room temperature curable organopolysiloxane composition and a cured product thereof.

[0002]

2. Description of the Related Art Room temperature curable organopolysiloxane compositions of the condensation curing type are used as adhesives for parts requiring vibration damping properties in the fields of electric / electronics, building materials, etc. In such applications, it is required that the curing rate is high and that the obtained cured product is an elastic body.

As a room temperature curable organopolysiloxane composition of the condensation curable type, the crosslinking rate has hitherto been improved by reducing the amount of the crosslinking agent as much as possible 1 by the hydrolysis of the hydrolyzable group introduced into the main component. A liquid type and a two-component type in which a crosslinking agent and a curing agent are separately packaged are known. However, although the one-pack type has a high curing rate from the surface, it requires a considerable time for deep curing. On the other hand, the two-part type has excellent deep-part curability, but the volume ratio or weight ratio of the two parts to be mixed is not 1: 1, so the workability of metering and mixing is poor, and it is suitable for automatic mixers. It has the drawback of being difficult to do. Furthermore, the two-component type has a narrow range of the addition amount of the cross-linking agent and the curing agent necessary for completely curing the deep portion, so that the addition amount should be strictly controlled or the water amount of the deep-curing agent should be adjusted. It is necessary to add

[0004]

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a room temperature curable organopolysiloxane composition and a cured product thereof, which have a fast curing rate, excellent deep curability and excellent workability. It is in.

[0005]

The present invention is a room temperature curable organopolysiloxane containing as a main component a hydrolyzable silyl group-containing organopolysiloxane and a polymer of a monomer having an ethylenically unsaturated double bond. In the composition, the moisture required for crosslinking and curing the former organopolysiloxane is generated in the composition by the reaction between the organic compound having a carbonyl group and the organic compound having a primary amino group, whereby the above-mentioned problems are solved. Could be solved.

The present invention provides (A) an organopolysiloxane whose molecular chain ends are blocked with a hydrolyzable silyl group, (B) a polymer of a monomer having an ethylenically unsaturated double bond, and (C) a carbonyl. Group-containing organic compound, (D) primary amino group-containing organic compound, and (E) room temperature curable organopolysiloxane composition containing the curing catalyst of component (A), and the composition A cured product obtained by curing is provided.

(A) Hydrolyzable silyl group-containing organopolysiloxane component (A) The organopolysiloxane of the component (A) has a molecular chain terminal blocked with a hydrolyzable silyl group and is the main component of the present invention.

Such an organopolysiloxane (A) has, for example, the general formula (1):

[Chemical 1]

(In the formula, a plurality of R ^1's may be the same or different and are, for example, alkyl groups such as methyl group, ethyl group and propyl group; for example, cycloalkyl groups such as cyclohexyl group; for example, vinyl group and allyl. An alkenyl group such as a group;
For example, an aryl group such as a phenyl group and a tolyl group; and a substituted or unsubstituted monovalent hydrocarbon group exemplified by a group in which the hydrogen atom of these groups is partially substituted with a halogen atom or the like. A plurality of R ^{2 s} may be the same or different and represent a substituted or unsubstituted monovalent hydrocarbon group, and the same groups as the above R ¹ are exemplified. R ³ represents a substituted or unsubstituted monovalent hydrocarbon group, and examples thereof include the same groups as R ¹ . When a plurality of R ^3's are present, they may be the same or different.
A plurality of X may be the same or different, and examples thereof include alkenyloxy groups such as isopropenyloxy group and isobutenyloxy group; examples include ketoxime groups such as dimethylketoxime and methylethylketoxime; examples include methoxy group and ethoxy. Group, alkoxy group such as butoxy group; for example, acyloxy group such as acetoxy group; amino group such as N-butylamino group, N, N-diethylamino group; aminoxy group such as N, N-diethylaminoxy group An amide group such as an N-methylacetamide group; and a hydrolyzable group exemplified by a carboxyl group and a hydroxyl group. k
And m may be the same or different and each is an integer of 0 to 2, and n is an integer of 10 or more. ) Is a compound represented by.

Among the organopolysiloxanes represented by the above general formula (1), X is preferably an alkenyloxy group. In the case of an organopolysiloxane where X is an alkenyloxy group, its hydrolysis and subsequent condensation produces a ketone which is one of the components (C) shown below. Therefore, the amount of the component (C) added can be reduced, and the amount of the condensate formed during hydrolysis can be controlled.

The organopolysiloxane of component (A) is 25
The viscosity at 0 ° C. is preferably 25 to 1000000 cSt, more preferably 500 to 100,000 cSt.

(B) The polymer component (B) of a monomer having an ethylenically unsaturated double bond exerts a reinforcing effect in the composition of the present invention as an organic filler.

As the component (B), a polymer obtained by polymerizing a known monomer having an ethylenically unsaturated double bond can be used without particular limitation. For example, polymers of olefins such as ethylene, propylene and butylene; polymers of halogen-substituted olefins such as vinyl chloride; polymers of vinyl esters such as vinyl acetate; for example, styrene, vinylnaphthalene, substituted ring atoms Polymers of aromatic group-containing vinyl compounds such as styrene having a group; for example, polymers of heterocycle-containing vinyl compounds such as vinylpyridine; unsaturated carboxylic acids such as acrylic acid and methacrylic acid; and ethyl acrylate, Polymers of esters and salts of unsaturated carboxylic acids such as butyl acrylate and methyl methacrylate; polymers of vinyl compounds containing amides such as acrylamide and methacrylamide; vinyl compounds containing nitriles such as acrylonitrile and methacrylonitrile. A polymer of Polymers of unsaturated aldehyde compounds such as rilaldehyde and methacrylaldehyde; for example, polymers of N-vinyl compounds such as N-vinylcarbazole, N-vinylpyrrolidone, N-vinylcaprolactam; for example, vinylidene fluoride, vinylidene chloride, Polymers of vinylidene compounds such as vinylidene cyanide; polymers of maleic acid, fumaric acid and their esters and anhydrides; polymers of stilbene, indene, coumarone; for example, allyl methacrylate, allyl acrylate, diallyl adipate, methallyl. Acrylate, methallyl methacrylate,
Polymers of polyfunctional olefin compounds such as vinyl acrylate, divinyl benzene, vinyl cyclohexene; for example, an acid selected from the group consisting of acrylic acid and methacrylic acid such as ethylene dimethacrylate, tetramethylene dimethacrylate, tetramethylene diacrylate and the like. Polymers of esters with polyhydric alcohols; for example, polymers of diene compounds such as 1,3-butadiene, isoprene, chloroprene; vinyltrimethoxysilane, vinyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ- Examples thereof include polymers of vinyl group-containing silicon compounds such as acryloxypropyltrimethoxysilane.

Preferred among these are ethyl acrylate, methyl methacrylate, butyl acrylate, styrene, vinylnaphthalene, propylene and butylene.

The above component (B) can be used either as a homopolymer or a copolymer obtained by copolymerizing two or more kinds of monomers. In that case, the structure of the polymer may be random, block, graft or the like. Any molecular weight can be used.

Among the polymers of component (B), when a polymer which is polymerized in the presence of component (A) and is dispersed in component (A) is used, especially in the composition of the present invention. The reinforcing effect is improved. The polymer in such a state is the component (B)
The monomer can be easily produced by polymerizing the monomer in component (A) or in a solution in which component (A) is dissolved in a suitable solvent by a known method.

The blending amount of the component (B) is preferably 20 to 250 parts by weight with respect to 100 parts by weight of the component (A).
A range of up to 170 parts by weight is preferred.

(C) Carbonyl group-containing organic compound The organic compound having a carbonyl group (C═O) of the component (C) is
It reacts with an organic compound having a primary amino group (-NH ₂ group) of the component (D) shown below to generate water which acts as a deep curing agent.

Examples of the component (C) include ketones such as acetone, methyl ethyl ketone, acetophenone and cyclohexanone; esters such as ethyl acetate, butyl acetate, methyl propionate, ethyl acrylate and butyrolactone; Amides such as formamide, diethylacetamide, butyrolactam; for example, carboxylic acids such as acetic acid, propionic acid, benzoic acid; silane coupling agents having a carbonyl group-containing moiety of these compounds as a functional group; various polymers having a carbonyl group, Examples thereof include oligomers. Among these compounds, acetone and cyclohexanone are preferable. The above-mentioned carbonyl group-containing compound
(C) can be used alone or in combination of two or more.

The blending amount of this component (C) is the above-mentioned components.
The amount is preferably 0.001 to 1 mol, and more preferably 0.01 to 0.1 mol, based on 100 parts by weight of the total of (A) and component (B). If the blending amount is too small, the composition does not exhibit sufficient deep-part curability at the time of curing, and if the blending amount is too large, the cured product obtained by curing the composition is soft and has reduced strength.

(D) Primary amino group-containing organic compound component (D) is a carbonyl group-containing organic compound as described above.
It has the property of reacting with (C) to generate water that acts as a deep-curing agent.

Examples of the organic compound (D) having a primary amino group include methylamine, ethylamine, butylamine, ethylenediamine, triethylenetetramine,
First of aniline and 4,4'-diaminodiphenyl ether
Primary amines, γ-aminopropyltriethoxysilane,
Primary amino group-containing silane compounds such as silane coupling agents having a primary amino group as a functional group such as γ-aminopropyltrimethoxysilane, aliphatic polyamines, primary amino group-containing alkylene oxide polymers, and Examples thereof include polymers and oligomers having a primary amino group such as primary amino group-containing polysiloxane.

Of these, amino group-containing organosilicon compounds such as primary amino group-containing silane compounds and primary amino group-containing polysiloxanes are preferable in that particularly good rubber elastic properties can be obtained. Such an amino group-containing organosilicon compound has a basic skeleton represented by the general formula (2):

[0024]

[Chemical 2]

(In each formula, R ⁴ is an alkyl group such as a methyl group or an ethyl group, an aryl group such as a phenyl group, an alkenyl group such as a vinyl group or an allyl group, a trifluoropropyl group, a methoxy group or an ethoxy group. , An alkoxy group such as an iropropoxy group, an amino group, an aminoxy group, an acetoxy group and the like are exemplified.) And the like. It is a compound in which an amino group is bound via an appropriate linking group. The structure of the amino group-containing organosilicon compound is linear, branched,
It may be cyclic or a combination of these structures, and their molecular weights are not particularly limited.

Specific examples of the above amino group-containing organosilicon compound include:

[Chemical 3]

[0027]

[Chemical 4]

Examples are those represented by structural formulas such as
Others, KF393, KF859, KF86, KF861, KF867, KF8
69, KF880, KF8002, KF8004, KF8005, KF864, KF86
Examples are those commercially available under the trade names of 5, KF868 and KF8003 (produced by Shin-Etsu Chemical Co., Ltd.).

The above-mentioned primary amino group-containing organic compound (D)
Can be used alone or in combination of two or more.

The amount of the component (D) blended is such that the primary amino group of the component (D) is relative to 1 mol of the carboxyl group of the component (C).
The amount is preferably in the range of 0.01 to 100 mol,
Considering the curing rate of the composition, long-term storage stability in an uncured state, economic efficiency, etc., the amount is preferably in the range of 0.1 to 5 mol.

(E) Hydrolyzable silyl group-containing organopoly
The curing catalyst component (E) for the siloxane (A) is a curing catalyst for the component (A), and for example, tin-based catalysts and titanium-based catalysts can be used. Specifically, tin naphthenate, tin caprylate, tin oleate, dibutyltin diacetate, dibutyltin dioctate, dibutyltin dilaurate, dibutyltin dioleate, diphenyltin diacetate, dibutyltin oxide, dibutyltin dimethoxide, dibutylbis (triethoxysiloxy). ) Tin, organic tin compounds such as dibutyltin benzyl malate, tetraisopropoxy titanium, tetra-n-butoxy titanium, tetrabis (2-
Examples include titanic acid esters such as ethylhexoxy) titanium, dipropoxybis (acetylacetonato) titanium, titanium isopropoxyoctylene glycol and titanium chelate compounds.

Further, a basic compound may be used in combination in order to enhance the activity of the catalyst. Specifically, amines such as octylamine and laurylamine, cyclic amines such as imidazoline, tetrahydropyrimidine, 1,8-diazabicyclo (5,4,0) -7-undecene and guanidinepropyltris (trimethylsiloxy). Examples thereof include guanidyl group-containing silane compounds such as silane and partial hydrolysates thereof, and guanidyl group-containing siloxanes.

The amount of the catalyst (E) compounded is preferably in the range of 0.1 to 10 parts by weight, relative to 100 parts by weight of the component (A). Considering this, the range of 0.5 to 5 parts by weight is particularly preferable.

Other Components In addition to the components (A) to (E), various components can be added to the room temperature curable composition of the present invention, if necessary. For example, storage stabilizers such as methyltrimethoxysilane, methyltripropenoxysilane, vinyltributanoxime silane, and methyltriacetoxysilane, fumed silica, precipitated silica, aluminum oxide, quartz powder, carbon powder, talc, bentonite, etc. Reinforcing agents, fibrous fillers such as asbestos, glass fibers and organic fibers, coloring agents such as pigments and dyes, red iron oxide, heat resistance improving agents such as cerium oxide, cold resistance improving agents, dehydrating agents, γ-glycidoxypropyl Examples thereof include an adhesion improver such as triethoxysilane, and a liquid reinforcing agent such as a reticulated polysiloxane composed of triorganosiloxy units and SiO ₂ units. These may be added in predetermined amounts as needed.

Preparation of Composition The composition of the present invention is a one-part composition by uniformly mixing the required amounts of each of the components (A) to (E) and optional components optionally added in a dry atmosphere. Obtained as a mold room temperature curable composition. At this time, the component (C) or (D) is mixed in a microencapsulated state to give a one-pack type room temperature curable composition having improved storage stability. It is also possible to use a two-liquid type in which the two liquids are separately packaged and mixed at the time of use. In the case of the two-liquid type, it is easy to set the mixing ratio of the two liquids to 1: 1 and workability is good. Also, the composition of the present invention usually cures easily in air, usually at 0 to 20 ° C.

Applications From the viewpoint of its rapid curing property and deep curing property, this composition is, for example, a sealing material for buildings, a coating material, a sealing material for electric and electronic parts, a potting material, a fiber treating agent, for automobiles, and construction. It is useful as an adhesive for electric appliances and electric appliances. In particular, it can be effectively used as an oil seal material for automobiles, which is required to have high fast-curing property and deep-curing property in the manufacturing process, and a sealing material and potting material for electric and electronic devices, which have recently been required to rationalize the process.

[0037]

In the composition of the present invention, upon curing, the carbonyl group contained in the component (C) and the primary amino group contained in the component (D) have the following formula:

[0038]

[Chemical 5]

Reacting to produce water,
The water is utilized in the system as a deep-curing agent, which greatly improves the fast-curing and deep-curing properties of the composition.

This has an advantage that it is easy to mix the two liquids in a ratio of 1: 1 when the two liquids are packed and mixed at the time of use, and further, in order to generate this water. The components to be added, that is, the organic compound having a C═O group and the organic compound having a primary amino group are both readily available, and thus are excellent in practicality.

[0041]

EXAMPLES Examples of the present invention will be given below. Synthesis Example 1 70 parts by weight of styrene and 60 parts by weight of n-butyl acrylate were added to t-butyl in 80 parts by weight of dimethylpolysiloxane having a viscosity of 700 cs, both ends of which were blocked with vinyldiisopropenoxysilyl groups. Copolymerization was carried out at 120 ° C. for 6 hours using peroxybenzoate as a polymerization initiator. The obtained mixture of the component (A) and the component (B) was used as a polymer A.

Synthetic Example 2 70 parts by weight of styrene and 60 parts by weight of n-butyl acrylate were added to 80 parts by weight of dimethylpolysiloxane having both ends of the molecular chain blocked with trimethoxysilyl groups and having a viscosity of 8000cs. Using peroxybenzoate as a polymerization initiator, 120 ° C
Was copolymerized for 6 hours. The obtained mixture of the component (A) and the component (B) was used as a polymer B.

Synthesis Example 3 70 parts by weight of styrene and 60 parts by weight of methyl methacrylate were added to t-butylperoxybenzoate in 80 parts by weight of dimethylpolysiloxane having both ends of the molecular chain blocked with trimethoxysilyl groups and having a viscosity of 900 cs. Copolymerization was carried out at 120 ° C. for 6 hours as a polymerization initiator. The obtained mixture of the component (A) and the component (B) was used as a polymer C.

Examples 1 to 5; Comparative Examples 1 to 3 In each of the Examples and Comparative Examples, compositions were prepared by mixing the components shown in Table 1 at the compounding ratio shown in Table 1. Next, each of the obtained compositions was molded into a sheet having a thickness of 2 mm and then left in an atmosphere of 20 ° C. and 60% RH. twenty four
After the lapse of time, the hardness, tensile strength, and elongation of each of the obtained cured products were measured according to JIS K 6301. The hardness was measured using a spring type hardness tester type A. The results are shown in Table 1.

Further, in order to evaluate the deep part curability, the depth
Each composition was placed in a 10 mm plastic container, and after 2 hours, the deep cured thickness (thickness from the surface of the cured layer) was measured. The results are shown in Table 1.

[0046]

[Table 1]

[0047]

The composition of the present invention is excellent in fast-curing property and deep-curing property, and is also excellent in workability. Therefore, in particular, it can be effectively used as an oil seal material for automobiles, which is required to have high rapid curability and deep curability in the manufacturing process, and a sealing material and potting material for electric and electronic, which have recently been required to rationalize the process. it can.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Masatoshi Arai, Masatoshi Arai, Hitomi, Matsuda-cho, Usui-gun, Gunma 10 Shin-Etsu Chemical Co., Ltd. Silicone Electronic Materials Research Laboratory

Claims (4)

[Claims] 1. An organopolysiloxane (A) having a chain end blocked with a hydrolyzable silyl group, (B) a polymer of a monomer having an ethylenically unsaturated double bond, and (C) a carbonyl group. A room temperature curable organopolysiloxane composition comprising: (D) an organic compound having a primary amino group, and (E) a curing catalyst of the above component (A). 2. The room temperature curable organopolysiloxane composition according to claim 1, wherein the hydrolyzable silyl group of the component (A) produces a ketone by hydrolysis. 3. The room-temperature-curable organopolysiloxane composition according to claim 1, wherein the component (B) is polymerized in the presence of the component (A) and is dispersed in the component (A). A composition that is coalesced. 4. A cured product obtained by curing the room temperature curable organopolysiloxane composition according to claim 1.